How to Check URL for proper format?

[thewird]

I was wondering how you check a URL in a variable to see that it is in proper format. What I mean by this is that it has no illegal characters for URL and can exist but doesn't mean it necessarily exists (don't need to check if it actually exists on the web). If anyone could help me with this, that would be great. Thanks.

thewird

[AndyB]

Copied from http://www.weberdev.com/get_example-4227.html

[code]
<?php
/*
The next code checks the following :

o URL starts with a-z, A-Z (e.g. http, ftp...)
o It is then followed by ://
o next we have more letters, numbers and special chars : a-z, A-Z, 0-9, -, _
o there must be at least one "."
o A URL can contain at it's end part the more special characters and this is
why the last part allows for more options such as ?, /, &, %, etc...
you may add/remove chars as needed to your code.
*/

// Assuming that the URL is received from a FORM by POST with the field name being "URL" the code
// Looks like this :

if(!preg_match("/^[a-zA-Z]+[:\/\/]+[A-Za-z0-9\-_]+\\.+[A-Za-z0-9\.\/%&=\?\-_]+$/i",$_POST[URL])) {
Echo"You must supply a valid URL.";
Exit();
}
?>[/code]

[thewird]

Thank you very much. It works great :).

thewird

[thewird]

Oh I just realized it allows for any urls. What I was really looking for and  wasn't quite clear was for domain name only, meaning something.extension (ie domain.com)

For the preg_match part i did...

preg_match("/^[A-Za-z0-9\-_]+\\.+[A-Za-z0-9-_]+$/i",$domainname)

However, I'm not sure what +$/i does. Could anyone help? THanks.

thewird

[thewird]

Anyone?

thewird

[redarrow]

Your getting a head start hear but relly you need to read the manual on regular exspestions


good luck


//if the format of the url is a www.xxxxxx.com

[code]
<?php

$url="www.phpfreaks.com";

if(!eregi("^[a-zA_Z]{3}.[a-zA-Z]{1,100}\.[a-zA-Z]{3}",$url)){

echo "incorrect web address";

}else{

echo "correct web address";
}

?>

[/code]



//if the format of the url is a http://www.xxxxxx.com

[code]
<?php

$url="http://www.phpfreaks.com";

if(!eregi("^(http://)[a-zA_Z]{3}.[a-zA-Z]{1,100}\.[a-zA-Z]{3}",$url)){

echo "incorrect web address";

}else{

echo "correct web address";
}

?>
[/code]

//if the format of the url is a www.xxxxxx.com but only a .com
[code]
<?php

$url="www.phpfreaks.com";

if(!eregi("^[a-zA_Z]{3}.[a-zA-Z]{1,100}\.(com)",$url)){

echo "incorrect web address";

}else{

echo "correct web address";
}

?>
[/code]

//if the format of the url is a www.xxxxxx.com but only a .com or .net
[code]
<?php

$url="www.phpfreaks.net";

if(!eregi("^[a-zA_Z]{3}.[a-zA-Z]{1,100}\.(com|net)",$url)){

echo "incorrect web address";

}else{

echo "correct web address";
}

?>
[/code]

[SharkBait]

$/i is for case-insensative I believe.

[thewird]

[quote author=SharkBait link=topic=104325.msg416292#msg416292 date=1155660310]
$/i is for case-insensative I believe.
[/quote]

Ok thanks. I think the code I posted above should do the trick then.

thewird